Contamination of human DNA samples with mouse DNA can lead to false detection
of XMRV-like sequences.

Background: In 2006, a novel gammaretrovirus, XMRV (xenotropic murine
leukemia virus-related virus), was discovered in some prostate tumors. A more recent
study indicated that this infectious retrovirus can be detected in 67% of patients
suffering from chronic fatigue syndrome (CFS), but only very few healthy controls
(4%). However, sever... read moreal groups have published to date that they could not identify
XMRV RNA or DNA sequences in other cohorts of CFS patients, while another group
detected murine leukemia virus (MLV)-like sequences in 87% of such patients, but only
7% of healthy controls. Since there is a high degree of similarity between XMRV and
abundant endogenous MLV proviruses, it is important to distinguish contaminating
mouse sequences from true infections. read less